ExamBro
ExamBro
JEE Mains · Physics · STD 12 - 9. Ray optics and optical instruments

The magnitudes of power of a biconvex lens (refractive index 1.5) and that of a plano-concave lens (refractive index \(=1.7\)) are same. If the curvature of plano-concave lens exactly matches with the curvature of back surface of the biconvex lens, then ratio of radius of curvature of front and back surface of the biconvex lens is ___________ .

  1. A 5 : 2
  2. B 5 : 12
  3. C 12 : 5
  4. D 2 : 5
Verified Solution

Answer & Solution

Correct Answer

(A) 5 : 2

Step-by-step Solution

Detailed explanation

\(\left| P _{ A }\right|=\left| P _{ B }\right|\) \(0.5\left(\frac{1}{ R _1}+\frac{1}{ R _2}\right)=\frac{0.7}{ R _2}\) \(\frac{5}{ R _1}=\frac{2}{ R _2}\) \(\frac{ R _1}{ R _2}=\frac{5}{2}\)
Same subject
Explore more questions on app